Transforming the ESP32 into a Software-Defined Radio with ESP-SDR Firmware

The ESP32 microcontroller has gained popularity for its versatility in various applications, ranging from IoT devices to advanced AI projects. Recently, the introduction of ESP-SDR firmware has opened up new possibilities by transforming the ESP32 into a fully functional Software-Defined Radio (SDR) without the need for extra hardware.

This innovative open-source firmware allows users to bypass the conventional Wi-Fi and Bluetooth functionalities of the ESP32, directly accessing its internal ADC signal chain. This enables the capture of raw I/Q baseband samples, which can then be transmitted to a computer via USB or UART. Users can visualize these samples as radio spectrums or waterfall displays, effectively turning compatible ESP32 models into cost-effective SDR receivers.

Key features of the ESP-SDR firmware include support for various ESP32 chips such as the ESP32, ESP32-C3, and ESP32-C5, among others, with a tuning range that nominally covers the 2.4 GHz ISM band and extends into the 5 GHz range. This development marks a significant step forward in making SDR technology more accessible to hobbyists and professionals alike.

Source: CNX Software – Embedded Systems News (https://www.cnx-software.com/2026/10/04/esp-sdr-firmware-turns-esp32-into-a-2-4-5-ghz-software-defined-radio-sdr/)